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      cite="mid:39094D58-3326-4339-84AA-26A5745F6F87@sdfe.dk">
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              <div class="">On 29 Oct 2018, at 20:20, Robb Main &lt;<a
                  href="mailto:rmain.mws@gmail.com" class=""
                  moz-do-not-send="true">rmain.mws@gmail.com</a>&gt;
                wrote:</div>
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                <div dir="ltr" class="">(…snip…) I'd consider the UTM
                  zone a part of the OUTPUT, whereas you seem to
                  consider it part of the required input (lat, long
                  &amp; UTM zone).
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                  <div class="">So in my case:</div>
                  <div class=""> in: lat &amp; long</div>
                  <div class="">out: UTM zone, easting &amp; northing.</div>
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                  <div class="">so the process would look more like:</div>
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                    <div class="">$ echo 6 51 | proj +proj=utm
                      +zone=auto</div>
                    <div class="">31    710488.86       5654109.18</div>
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    <p>Actually such operation already exists in EPSG database (not sure
      if it exists in Proj4 however). This is the Operation Method
      EPSG::9824 - Transverse Mercator Zoned Grid System. The output is
      basically:</p>
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      <p>E = Z*10^6 + (result of projection for zone Z)</p>
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    <p>This is not widely used however.</p>
    <p>    Martin</p>
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